MC68020RC20E Freescale Semiconductor, MC68020RC20E Datasheet - Page 164

• Manufacturer Part Number: MC68020RC20E
• Description: IC MICROPROCESSOR 32BIT 114-PGA
• Manufacturer: Freescale Semiconductor

Specifications of MC68020RC20E

• Processor Type: M680x0 32-Bit
• Speed: 20MHz
• Voltage: 5V
• Mounting Type: Surface Mount
• Package / Case: 114-PGA
• Family Name: M68000
• Device Core: ColdFire
• Device Core Size: 32b
• Frequency (max): 20MHz
• Instruction Set Architecture: RISC
• Supply Voltage 1 (typ): 5V
• Operating Supply Voltage (max): 5.25V
• Operating Supply Voltage (min): 4.75V
• Operating Temp Range: 0C to 70C
• Operating Temperature Classification: Commercial
• Mounting: Through Hole
• Pin Count: 114
• Package Type: PGA
• Lead Free Status / RoHS Status: Contains lead / RoHS Compliant
• Features: -
• Lead Free Status / Rohs Status: Compliant

After evaluating the condition, the coprocessor returns a true/false indicator to the main
processor by placing a null primitive (refer to 7.4.4 Null Primitive) in the response CIR.
The main processor completes the coprocessor instruction execution when it receives the
condition indicator from the coprocessor.
MOTOROLA
OPERATION WORD
CO
1) PERFORM SERVICE REQUESTED BY RESPONSE
PRIMITIVE
RETURNED IN THE RESPONSE CIR
M1
M2
M3
FROM RESPONSE CIR
2) IF (COPROCESSOR RESPONSE PRIMITIVE
INDICATES "COME AGAIN") GO TO M3
(SEE NOTE)
M4
ON THE TRUE/FALSE CONDITION INDICATOR
NOTE: All coprocessor response primitives, except the Null primitive, that allow the "Come Again" primitive attribute
NDITION CIR
WRITE COPROCESSOR CONDITION SELECTOR TO
RECOGNIZE COPROCESSOR INSTRUCTION F-LINE
READ COPROCESSOR RESPONSE PRIMITIVE CODE
COMPLETE EXECUTION OF INSTRUCTION BASED
must indicate "Come Again" when used during the execution of a conditional category instruction. If a "Come
Again" attribute is not indicated in one of these primitives, the main processor will initiate protocol violation
exception processing (see 7.5.2.1 Protocol Violations).
MAIN PROCESSOR
Figure 7-8. Coprocessor Interface Protocol
Freescale Semiconductor, Inc.
for Conditional Category Instructions
For More Information On This Product,
Go to: www.freescale.com
M68020 USER’S MANUAL
COMMAND EXECUTION
DO STEPS 1) AND 2) BELOW
1) REQUEST SERVICE BY PLACING APPROPRIATE
2) RECEIVE SERVICE FROM MAIN PROCESSOR
CONDITION INDICATOR IN RESPONSE CIR
C1
C2
C3
C4
DECODE COMMAND WORD AND INITIATE
WHILE (MAIN PROCESSOR SERVICE IS REQUIRED)
COMPLETE CONDITION EVALUATION
REFLECT "NO COME AGAIN" STATUS WITH TRUE/FALSE
RESPONSE PRIMITIVE CODE IN RESPONSE CIR
COPROCESSOR
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